High-frequency electrosurgery belongs to such techniques that are now indispensable in performing most diverse operative procedures in general surgery, onco- and neurosurgery, gastoenterology, urology, ophthalmosurgery, and in many other branches of clinical medicine.
High-frequency electrosurgery is understood to mean a method of surgical effect with an r.f. current produced on the tissue of a patient's body with the purpose of its dissecting or coagulation. The method is based on physical and chemical processes proceeding in body tissues and evoked chiefly by the diathermic current effect.
High-frequency electrosurgery falls into two types, viz, monopolar and bipolar.
In case of monopolar electrosurgery one of the electrodes is active since the maximum current density is developed thereon, whereby this electrode is a working tool, while the other (auxiliary) electrode is passive.
In case of bipolar electrosurgery both of the electrodes are active and hence serve as working tools.
One of the most urgent problems in surgery up till now is a reliable, quick and high-quality arrest of bleeding in traumatic lesions of tissues, especially parenchymatous ones, such as the liver, kidney, spleen, and the like, as well as the arrest of bleeding from major blood vessels during preplanned surgical procedures.
Known in the present state of the art is a wide variety of bipolar electrosurgical instruments, e.g., forceps, in particular those for blood vessel coagulation (cf., e.g., an advertisement prospectus "Chirrurgie Zubehor ERBE elektromedizinsche Gerate").
Such instruments consist largely of two arms insulated from each other and provided with current-cunducting working jaws which are for catching blood vessels, while high-frequency current is supplied to both of the arms. However, such instruments fail to reliably catch and grip a blood vessel seated deeply in the parenchyma upon its contraction after having been severed, while any further attempt to catch the vessel inflicts mechanical damage upon still greater areas of the surrounding tissues.
Moreover, said instruments produce a large coagulation-affected area of tissues surrounding the vessel operated upon, and the coagulated tissue or thrombus that has stuck to the instrument working surface, is liable to be torn away when withdrawing the instrument after caogulation.
In addition, the instruments discussed above fail to simultaneously expose bloodlessly and catch mechanically and reliably a nonopened vessel seated deeply in the bulk of a parenchymatous organ.